This invention relates to optical filters, and more particularly concerns a color enhancing filter which will improve human eye vision under all lighting environments including extreme lighting environments.
Extreme lighting environments generally involve either very low or very high levels of light. In either environment, it is difficult for the human eye to accurately visualize objects. For example, this difficulty presents a particular challenge for law enforcement agencies, the military and everyday citizens who must perform activities, such as travel or navigation, under low level lighting conditions.
To overcome the absence of vision under low level environments, the military and private industry have developed active vision enhancing devices. However, these devices require the use of an electronic mechanism to amplify very low levels of light. The amplified light is then converted into images on a cathode tube or other device for viewing by the human eye.
To enhance vision under bright light environments, traditional smoke gray eye glass lenses have been generally used. However, the smoke gray lenses act to reduce the total amount of light that reaches the eye, thereby interfering with vision focus and accuracy. Moreover, the darkening effects of the smoke gray lenses may cause the eye to dilate. Unless ultraviolet protection is additionally provided, the smoke gray lenses, alone, permit additional and harmful ultraviolet radiation emitted from a light source to reach the eyes.
It is the general object of the present invention to improve human eye vision under all lighting environments including extreme lighting environments.
It is another object of this invention to improve human eye vision by employing a color enhancing filter under low level light environments with or without the aid of light amplification devices.
It is yet another object of this invention to improve human eye vision by employing a color enhancing filter under brightly illuminated environments.
It is a further object to provide a color enhancing filter which will not deteriorate or change optical properties even long after its manufacture, or after extensive use.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings. Throughout the drawings, like reference numerals refer to like parts.